# Draft California 2012 Integrated Report( 303(d) List/305(b) Report)

# Supporting Information

## Regional Board 6 - Lahontan Region

Water Body Name: | Dressler Ditch
Water Body ID: | CAR6322001020110223173539
Water Body Type: | River & Stream

DECISION ID | 32080 | Region 6
Dressler Ditch

Pollutant: | Turbidity
Final Listing Decision: | Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: | New Decision
Revision Status | Revised
Impairment from Pollutant or Pollution: | Pollutant
Regional Board Staff Conclusion: | This pollutant is being considered for placement on the section 303(d) list under section 3.2 of the Listing Policy. Under section 3.2 a single line of evidence is necessary to assess listing status. One line of evidence is available in the administrative record to assess this pollutant. Six of six samples exceed the water quality objective, which is 2 NTU based on a mean of monthly means value. Samples were collected for six years in 2000, 2001, 2007-2010. Over the 6 year period, between 1-5 monthly means were averaged to calculate the annual mean. For the 6 years of sampling, samples were never collected during the low flow months of Sept - December, and samples were always collected in May. This sampling frequency may bias the annual average to a higher value due to sampling during high runoff periods that typically produce more turbidity. This sampling frequency is not sufficient to represent the seasonal and annual fluctuations of turbidity and streamflow within this waterbody, which is why the use rating for this LOE is considered "insufficient information" instead of "not supporting." Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the section 303(d) list in the Water Quality Limited Segments category. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used do not satisfy the data quantity requirements of section 6.1.5 of the Policy. The sampling frequency is not sufficient to represent the seasonal and annual fluctuations of turbidity and streamflows within this waterbody. 3. Six of six samples exceed the objective of 2 NTU, which is based on a MOMM value and this exceeds the allowable frequency listed in Table 3.2 of the Listing Policy; however, listing is not recommended at this time because the dataset is not temporally representative. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
Regional Board Staff Decision Recommendation: | After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because it cannot be determined if applicable water quality standards are not being exceeded.

Line of Evidence (LOE) for Decision ID 32080, Turbidity | Region 6
Dressler Ditch
LOE ID: | 32452
Pollutant: | Turbidity
LOE Subgroup: | Pollutant-Water
Matrix: | Water
Fraction: | None
Beneficial Use: | Cold Freshwater Habitat
Number of Samples: | 6
Number of Exceedances: | 6
Data and Information Type: | PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: | Data were collected over 6 years. During those 6 years, the mean of monthly mean exceeded 2 NTU every year.
Data Reference: | Data for temperature, nutrients, and bacteria in Heavenly Valley Creek (USFS boundary to Trout Creek) and various water bodies in Alpine County, Jul 1980-Jun. 2010
SWAMP Data: | Non-SWAMP
Water Quality Objective/Criterion: | From the Lahontan Regional Water Quality Control Plan: The turbidity shall not be raised above 2 NTU mean of monthly means value. (This objective is approximately equal to the State of Nevada standard of 2 NTU sample mean) .
Objective/Criterion Reference: | Water Quality Control Plan for the Lahontan Region (as amended)
Evaluation Guideline: |
Guideline Reference:
Spatial Representation: | Sample collected at the following locations: D-3-Dressler Ditch @ Indian Creek Reservoir Inlet D-3 24-Hr-Dressler Ditch @ Indian Creek Reservoir Inlet D-7-Dressler Ditch below Road Crossing D-8-Dressler Ditch above sand trap
Temporal Representation: | Samples collected between 5/25/2000 and 5/4/2010.
Environmental Conditions: |
QAPP Information: | South Tahoe Public Utility District Laboratory Quality Assurance Program (by Terry Powers, Laboratory Director). March 30, 2009.
QAPP Information Reference(s):

DECISION ID | 32081 | Region 6
Dressler Ditch

Pollutant: | pH
Final Listing Decision: | Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: | New Decision
Revision Status | Revised
Impairment from Pollutant or Pollution: | Pollutant
Regional Board Staff Conclusion: | This pollutant is being considered for placement on the section 303(d) list under section 3.2 of the Listing Policy. Under section 3.2 a single line of evidence is necessary to assess listing status. One line of evidence is available in the administrative record to assess this pollutant. The Lahontan Basin Plan's narrative pH objective is an antidegradation-based objejctive that requires that there be no change greater than 0.5 pH units in waters designated for COLD and WARM beneficial uses. ( A pH range of 6.5 to 8.5 units applies to "all other waters.") Listing Policy section 3.10 contains directions for assessment based on trends in water quality. Though the LOE (33845) associated with this decision finds that three of the 115 samples exceed the water quality objective, this can not be determined with certainty because baseline condition (normal ambient pH) has not been established for this waterbody. Staff recommend some trend analysis be completed on this data set before next listing cycle to determine the normal ambient pH for this waterbody. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the section 303(d) list in the Water Quality Limited Segments category. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. It can not be determined with certainty if three of 115 samples exceeded the objective because the water quality objective requires that a normal ambient pH be established for this waterbody in order to determine protection of the COLD beneficial use. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
Regional Board Staff Decision Recommendation: | After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because it cannot be determined if applicable water quality standards are not being exceeded.

Line of Evidence (LOE) for Decision ID 32081, pH | Region 6
Dressler Ditch
LOE ID: | 33845
Pollutant: | pH
LOE Subgroup: | Pollutant-Water
Matrix: | Water
Fraction: | Dissolved
Beneficial Use: | Cold Freshwater Habitat
Number of Samples: | 115
Number of Exceedances: | 3
Data and Information Type: | PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: | Numeric data generated from 115 minimums and maximums of pH data had 3 exceedences.
Data Reference: | Data for temperature, nutrients, and bacteria in Heavenly Valley Creek (USFS boundary to Trout Creek) and various water bodies in Alpine County, Jul 1980-Jun. 2010
SWAMP Data: | Non-SWAMP
Water Quality Objective/Criterion: | In fresh waters with designated beneficial uses of COLD or WARM, changes in normal ambient pH levels shall not exceed 0.5 pH units. For all other waters of the Region, the pH shall not be depressed below 6.5 nor raised above 8.5. The Regional Board recognizes that some waters of the Region may have natural pH levels outside of the 6.5 to 8.5 range. Compliance with the pH objective for these waters will be determined on a case-by-case basis. [There is no site specific objective for pH for this water body]
Objective/Criterion Reference: | Water Quality Control Plan for the Lahontan Region (as amended)
Evaluation Guideline: |
Guideline Reference:
Spatial Representation: | Samples were collected from the following stations: D-3, D-7, and D-8.
Temporal Representation: | Samples were collected once a month from January 2000 to May 2010.
Environmental Conditions: |
QAPP Information: | SWAMP QAPP
QAPP Information Reference(s): | Surface Water Ambient Monitoring Program Quality Assurance Program Plan

DECISION ID | 32075 | Region 6
Dressler Ditch

Pollutant: | Chloride
Final Listing Decision: | Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: | New Decision
Revision Status | Original
Impairment from Pollutant or Pollution: | Pollutant
Regional Board Staff Conclusion: | This pollutant is being considered for placement on the section 303(d) list under section 3.2 of the Listing Policy. Under section 3.2 a single line of evidence is necessary to assess listing status. One line of evidence is available in the administrative record to assess this pollutant. None of the sample exceeds the water quality objective. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the section 303(d) list in the Water Quality Limited Segments category. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. The single sample did not exceed the objective and this sample size is insufficient to determine with the power and confidence of the Listing Policy if standards are not met. A minimum of 26 samples is needed for application of table 3.2. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
Regional Board Staff Decision Recommendation: | After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because it cannot be determined if applicable water quality standards are not being exceeded.

Line of Evidence (LOE) for Decision ID 32075, Chloride | Region 6
Dressler Ditch
LOE ID: | 32200
Pollutant: | Chloride
LOE Subgroup: | Pollutant-Water
Matrix: | Water
Fraction: | None
Beneficial Use: | Cold Freshwater Habitat
Number of Samples: | 1
Number of Exceedances: | 0
Data and Information Type: | PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: | Data were collected for one year in 2000. For that year, the annual average did not exceed 1.0 mg/L.
Data Reference: | Data for temperature, nutrients, and bacteria in Heavenly Valley Creek (USFS boundary to Trout Creek) and various water bodies in Alpine County, Jul 1980-Jun. 2010
SWAMP Data: | Non-SWAMP
Water Quality Objective/Criterion: | The site-specific objective in Lahontan Basin Plan Table 3-14 is 2.5 mg/L as a mean of monthly means. The objective for West Fork Carson River at Stateline apply under the Tributary Rule.
Objective/Criterion Reference: | Water Quality Control Plan for the Lahontan Region (as amended)
Evaluation Guideline: |
Guideline Reference:
Spatial Representation: | Sample collected at the following locations: D-3-Dressler Ditch @ Indian Creek Reservoir Inlet D-3 24-Hr-Dressler Ditch @ Indian Creek Reservoir Inlet
Temporal Representation: | Samples collected between 5/25/2000 and 7/26/2000.
Environmental Conditions: |
QAPP Information: | South Tahoe Public Utility District Laboratory Quality Assurance Program (by Terry Powers, Laboratory Director). March 30, 2009.
QAPP Information Reference(s):

DECISION ID | 32076 | Region 6
Dressler Ditch

Pollutant: | Oxygen, Dissolved
Final Listing Decision: | Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: | New Decision
Revision Status | Original
Impairment from Pollutant or Pollution: | Pollutant
Regional Board Staff Conclusion: | This pollutant is being considered for placement on the section 303(d) list under section 3.2 of the Listing Policy. Under section 3.2 a single line of evidence is necessary to assess listing status. One line of evidence is available in the administrative record to assess this pollutant. One of the 15 samples exceeds the water quality objective. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the section 303(d) list in the Water Quality Limited Segments category. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. One of 15 samples exceeds the objective but this sample size is insufficient to determine with the power and confidence of the Listing Policy if standards are not met. A minimum of 26 samples is needed for application of table 3.2. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
Regional Board Staff Decision Recommendation: |

Line of Evidence (LOE) for Decision ID 32076, Oxygen, Dissolved | Region 6
Dressler Ditch
LOE ID: | 32450
Pollutant: | Oxygen, Dissolved
LOE Subgroup: | Pollutant-Water
Matrix: | Water
Fraction: | None
Beneficial Use: | Cold Freshwater Habitat
Number of Samples: | 15
Number of Exceedances: | 1
Data and Information Type: | PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: | Data were collected during 15 months on six different years (2000, 2001, 2007, 2008, 2009, and 2010). One of the 15 monthly averages was below 6.5 mg/L during this time. It should also be noted that none of the samples were below the 4.0 mg/L daily minimum (table 3-6).
Data Reference: | Data for temperature, nutrients, and bacteria in Heavenly Valley Creek (USFS boundary to Trout Creek) and various water bodies in Alpine County, Jul 1980-Jun. 2010
SWAMP Data: | Non-SWAMP
Water Quality Objective/Criterion: | From Table 3-6 of the Lahontan Regional Water Quality Control Plan (for COLD): 6.5 mg/L (30 Day Mean).
Objective/Criterion Reference: | Water Quality Control Plan for the Lahontan Region (as amended)
Evaluation Guideline: |
Guideline Reference:
Spatial Representation: | Sample collected at the following locations: D-3-Dressler Ditch @ Indian Creek Reservoir Inlet D-3 24-Hr-Dressler Ditch @ Indian Creek Reservoir Inlet D-7-Dressler Ditch below Road Crossing D-8-Dressler Ditch above sand trap
Temporal Representation: | Samples collected between 6/13/2000 and 5/4/2010.
Environmental Conditions: |
QAPP Information: | South Tahoe Public Utility District Laboratory Quality Assurance Program (by Terry Powers, Laboratory Director). March 30, 2009.
QAPP Information Reference(s):

DECISION ID | 32077 | Region 6
Dressler Ditch

Pollutant: | Specific Conductance
Final Listing Decision: | Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: | New Decision
Revision Status | Original
Impairment from Pollutant or Pollution: | Pollutant
Regional Board Staff Conclusion: | This pollutant is being considered for placement on the section 303(d) list under section 3.2 of the Listing Policy. Under section 3.2 a single line of evidence is necessary to assess listing status. One line of evidence is available in the administrative record to assess this pollutant. None of the 104 samples exceed the water quality objective (MCL of 900 uS/cm.) Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the section 303(d) list in the Water Quality Limited Segments category. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. None of 104 samples exceeded the objective and this does not exceed the allowable frequency listed in Table 3.2 of the Listing Policy. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
Regional Board Staff Decision Recommendation: | After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because applicable water quality standards are not being exceeded.

Line of Evidence (LOE) for Decision ID 32077, Specific Conductance | Region 6
Dressler Ditch
LOE ID: | 32449
Pollutant: | Specific Conductance
LOE Subgroup: | Pollutant-Water
Matrix: | Water
Fraction: | None
Beneficial Use: | Municipal & Domestic Supply
Number of Samples: | 104
Number of Exceedances: | 0
Data and Information Type: | PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: | There were 104 samples, none of which exceeded 900 uS/cm.
Data Reference: | Data for temperature, nutrients, and bacteria in Heavenly Valley Creek (USFS boundary to Trout Creek) and various water bodies in Alpine County, Jul 1980-Jun. 2010
SWAMP Data: | Non-SWAMP
Water Quality Objective/Criterion: | California Maximum Contaminant Levels (MCLs) apply to ambient waters under the Lahontan Basin Plan's "Chemical Constituents" objective. The MCL for specific conductance is 900 microsiemens per centimeter (uS/cm).
Objective/Criterion Reference: | Maximum Contaminant Levels for organic and inorganic chemicals. CCR
Evaluation Guideline: |
Guideline Reference:
Spatial Representation: | Sample collected at the following locations: D-3-Dressler Ditch @ Indian Creek Reservoir Inlet D-3 24-Hr-Dressler Ditch @ Indian Creek Reservoir Inlet D-7-Dressler Ditch below Road Crossing D-8-Dressler Ditch above sand trap
Temporal Representation: | Samples collected between 1/11/2000 and 5/4/2010.
Environmental Conditions: |
QAPP Information: | South Tahoe Public Utility District Laboratory Quality Assurance Program (by Terry Powers, Laboratory Director). March 30, 2009.
QAPP Information Reference(s):

DECISION ID | 32078 | Region 6
Dressler Ditch

Pollutant: | Sulfates
Final Listing Decision: | Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: | New Decision
Revision Status | Original
Impairment from Pollutant or Pollution: | Pollutant
Regional Board Staff Conclusion: | This pollutant is being considered for placement on the section 303(d) list under section 3.2 of the Listing Policy. Under section 3.2 a single line of evidence is necessary to assess listing status. One line of evidence is available in the administrative record to assess this pollutant. None of the two sample exceeds the water quality objective, which is a site-specific objective for sulfate of 2.0 mg/L as a mean of monthly means (applied through the Tributary Rule for West Fork Carson River at Stateline). Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the section 303(d) list in the Water Quality Limited Segments category. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. None of two samples exceeded the objective and this sample size is insufficient to determine with the power and confidence of the Listing Policy if standards are not met. A minimum of 26 samples is needed for application of table 3.2. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
Regional Board Staff Decision Recommendation: | After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because it cannot be determined if applicable water quality standards are not being exceeded.

Line of Evidence (LOE) for Decision ID 32078, Sulfates | Region 6
Dressler Ditch
LOE ID: | 32436
Pollutant: | Sulfates
LOE Subgroup: | Pollutant-Water
Matrix: | Water
Fraction: | None
Beneficial Use: | Cold Freshwater Habitat
Number of Samples: | 2
Number of Exceedances: | 0
Data and Information Type: | PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: | Data were collected for two years (2000 and 2001). For both years the annual average did not exceed 2.0 mg/L.
Data Reference: | Data for temperature, nutrients, and bacteria in Heavenly Valley Creek (USFS boundary to Trout Creek) and various water bodies in Alpine County, Jul 1980-Jun. 2010
SWAMP Data: | Non-SWAMP
Water Quality Objective/Criterion: | The site-specific objective for sulfate is 2.0 mg/L as a mean of monthly means (applied through the Tributary Rule for West Fork Carson River at Stateline). See Basin Plan Table 3-14.
Objective/Criterion Reference: | Water Quality Control Plan for the Lahontan Region (as amended)
Evaluation Guideline: |
Guideline Reference:
Spatial Representation: | Sample collected at the following locations: D-3-Dressler Ditch @ Indian Creek Reservoir Inlet D-3 24-Hr-Dressler Ditch @ Indian Creek Reservoir Inlet
Temporal Representation: | Samples collected between 5/25/2000 and 5/8/2001.
Environmental Conditions: |
QAPP Information: | South Tahoe Public Utility District Laboratory Quality Assurance Program (by Terry Powers, Laboratory Director). March 30, 2009.
QAPP Information Reference(s):

DECISION ID | 32079 | Region 6
Dressler Ditch

Pollutant: | Temperature, water
Final Listing Decision: | Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: | New Decision
Revision Status | Original
Impairment from Pollutant or Pollution: | Pollutant
Regional Board Staff Conclusion: | This pollutant is being considered for placement on the section 303(d) list under section 3.2 of the Listing Policy. Under section 3.2 a single line of evidence is necessary to assess listing status. One line of evidence is available in the administrative record to assess this pollutant. Five of the 95 samples exceed the water quality objective. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the section 303(d) list in the Water Quality Limited Segments category. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. Five of 95 samples exceeded the objective and this does not exceed the allowable frequency listed in Table 3.2 of the Listing Policy. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
Regional Board Staff Decision Recommendation: | After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because applicable water quality standards are not being exceeded.

Line of Evidence (LOE) for Decision ID 32079, Temperature, water | Region 6
Dressler Ditch
LOE ID: | 31706
Pollutant: | Temperature, water
LOE Subgroup: | Pollutant-Water
Matrix: | Water
Fraction: | None
Beneficial Use: | Cold Freshwater Habitat
Number of Samples: | 95
Number of Exceedances: | 5
Data and Information Type: | PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: | Five of the 68 samples exceeded the evaluation guideline for temperature in this water body.
Data Reference: | Data for temperature, nutrients, and bacteria in Heavenly Valley Creek (USFS boundary to Trout Creek) and various water bodies in Alpine County, Jul 1980-Jun. 2010
SWAMP Data: | Non-SWAMP
Water Quality Objective/Criterion: | The natural receiving water temperature of all waters shall not be altered unless it can be demonstrated to the satisfaction of the Regional Board that such an alteration in temperature does not adversely affect the water for beneficial uses. For waters designated WARM, water temperature shall not be altered by more than five degrees Fahrenheit above or below the natural temperature. For waters designated COLD, the temperature shall not be altered.
Objective/Criterion Reference: | Water Quality Control Plan for the Lahontan Region (as amended)
Evaluation Guideline: | Inland Fishes of California (Moyle 1976) states that for rainbow trout the optimum range for growth and completion of most life stages is 13-21 degrees C (page 129).
Guideline Reference: | Fish introductions in CA: History and impact on native fishes. Davis, CA: University of CA, Davis
Spatial Representation: | Samples were collected at the following locations in this water body: Dressler Ditch @ Indian Creek Reservoir Inlet Dressler Ditch below Road Crossing Dressler Ditch above sand trap
Temporal Representation: | Samples collected between 7/8/1980 and 6/2/2010.
Environmental Conditions: |
QAPP Information: | South Tahoe Public Utility District Laboratory Quality Assurance Program by Terry Powers, Laboratory Director (March 30, 2009)
QAPP Information Reference(s):